Hello,

This is my first post ;)

Perhaps this snippet of code is also convenient for a better understanding. I always like to print references in order to understand such things:

#!/usr/bin/perl

use strict;
use warnings;

use feature qw/say/;

my @array = (1, 2, 4, 8, 16, 32, 64, 128);

foreach my $elem (@array)
{
    say \$elem; # this *doesn't* print a unique number for all iterati
+ons!

    $elem *= 2;
}

say join(', ', @array);

say join(', ', map(\$_, @array)); # ..surprisingly familiar!

@array = qw/x y z/;

say join(', ', @array);

say join(', ', map(\$_, @array)); # ..surprisingly familiar too!

say \@array[0];
[download]

The output at my machine is:

SCALAR(0x8153220)
SCALAR(0x8153360)
SCALAR(0x8153100)
SCALAR(0x817bcb8)
SCALAR(0x817bcc8)
SCALAR(0x818ea18)
SCALAR(0x81886d0)
SCALAR(0x8188fd0)
2, 4, 8, 16, 32, 64, 128, 256
SCALAR(0x8153220), SCALAR(0x8153360), SCALAR(0x8153100), SCALAR(0x817b
+cb8), SCALAR(0x817bcc8), SCALAR(0x818ea18), SCALAR(0x81886d0), SCALAR
+(0x8188fd0)
x, y, z
SCALAR(0x8153220), SCALAR(0x8153360), SCALAR(0x8153100)
SCALAR(0x8153220)
[download]

edit: this may also be of interest

my $i = 123;

say $i . ' ' . \$i;

foreach $i (1 .. 3)
{
    say $i . ' ' . \$i;
}

say $i . ' ' . \$i;
[download]

output:

123 SCALAR(0x817bd18)
1 SCALAR(0x8153220)
2 SCALAR(0x8153220)
3 SCALAR(0x8153220)
123 SCALAR(0x817bd18)
[download]

The reason why the scalars are the same inside the foreach in this particular occasion is because I'm now iterating over a list and not an array. I've always assumed that there is a difference, and that lists only exist in Perl source code and that they are solely used for initialization of other things such as arrays (and hashes). Is this correct?

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